The Hidden Cost of Eating Shrimp

Shrimp dishes have become a staple food in many households and restaurants around the world, leading to an explosion in shrimp production of over 600% in the past 50 years. But this growth comes at a cost.

Shrimp has been caught and consumed around the world for centuries in many parts of the world, but in the past 50 years, its production has skyrocketed.¹ This surge, fuelled by international trade agreements, globalisation, dietary shifts, and technological advances, resulted in a historic production peak of 10 million tonnes globally in 2021, representing a doubling of production in the last decade alone.^1,2 Notably, Ecuador, India, Vietnam, Indonesia, and China emerged as the top exporters, while the USA, China, Japan, Spain, and France dominated as leading importers.² Unfortunately, the industry's fast growth comes with social and environmental costs that demand urgent attention and resolution.

Farmed and wild-caught shrimp production in the past 70 years. Graph by Maria Pinto

Wild-caught shrimp

While the global catch of shrimp is primarily done by large industrial fishing operations, some of the largest shrimp fisheries still rely on small-scale, non-motorized methods.³ Trawling, the most common method used in industrial shrimp fisheries, as well as in some small-scale operations, is considered one of the most environmentally destructive fishing methods worldwide.⁴

Bycatch

Trawling, involving the dragging of a net along the seabed, contributes significantly to the world's bycatch, with shrimp trawling accounting for up to 27% of the global total of bycatch across all species.¹ In developed regions, most of this bycatch is thrown back into the ocean. This happens when the species caught are either protected, not commercially valuable, the individuals are smaller than the legally authorised size, the assigned fishing quota has been reached, or simply because of high grading standards.

In regions in Southeast Asia, a large part of the bycatch is repurposed.³ In cases where most bycatch dies, repurposing it might be the best outcome. However, determining whether or not the animals would have died if released back into the ocean is a difficult task. Additionally, the collateral damage extends to endangered species like sharks, sea turtles, and marine mammals, where bycatch is a primary driver of their decline.

Efforts to avoid bycatch include introducing bycatch reduction devices (BRDs) in nets and modifications like escape ‘windows’ designed to exclude larger marine animals while still allowing shrimp to be caught. However, despite their apparent effectiveness, the global implementation of BRDs remains inconsistent, and the lack of proper monitoring in many regions worldwide makes it difficult to determine the actual success rate of existing mitigation methods and how often they are employed.¹

Commercial fishing trawler in the Sea of Cortez, Mexico. Credit: Grandriver, Getty

Habitat destruction

Trawling is also responsible for the irreversible destruction of sensitive seafloor habitats such as coral reefs, sponge grounds, seagrass meadows, and gorgonian gardens.⁴ While trawling often occurs over open muddy and sandy bottoms where it might have a comparatively lower impact due to faster recovery rates and lower biodiversity of this habitat, it still alters the biogeochemical properties of the seabed and disrupts any organisms residing there.³

Soft bottoms might be able to recover their geochemical and biological characteristics relatively faster than other habitats after being trawled.⁵ However, their recovery might still take years, and many of these areas are subjected to repeated trawling multiple times a year, preventing any potential recovery.³ This cycle of destruction directly impacts the commercially caught shrimp and fish, which depend on these habitats for crucial aspects of their life cycle, from feeding to reproduction and growth.⁴ Some small-scale, artisanal fishers employ less environmentally damaging practices, like cast nets, traps, and lower impact ‘suripera nets’.⁶ However, to sustain the current high shrimp demand, most industrial shrimp fishing worldwide is done by trawling, which yields larger catches. Despite significant interest in developing alternative gears to replace shrimp trawling operations, little progress has been achieved in finding viable industrial-scale alternatives, resulting in continued reliance on trawl gear as the primary method for commercial shrimp species.¹

Farmed shrimp

The latter half of the 20th century witnessed a pivotal shift from wild-caught to farmed shrimp, catalysed by government incentives and commercial investments in countries like Thailand, China, and Vietnam.¹ The development of shrimp aquaculture in Southeast Asia revolutionised the industry, providing increased production and a more consistent shrimp supply to a growing demand by European and American restaurants and households. Ultimately, shrimp farming has become a cornerstone of economic activity in developing regions.⁷

While farming offers a potential solution to bycatch and habitat destruction associated with trawling, it comes with its own set of associated costs.

Mangrove destruction

One of the major environmental concerns tied to shrimp farming is mangrove destruction. Mangrove forests act as crucial coastal buffers and protect against erosion, storm surges, and tsunamis. They also serve as vital habitats for numerous species and breeding grounds for commercially valuable fish and shrimp.⁸

Situated in sheltered estuarine areas with nutrient-rich coastal waters and abundant wild shrimp juveniles, many saw mangroves as ideal locations for seafood farming.⁹ Between 1980 and 2005, the largest aquaculture producers, Indonesia, Brazil, India, Bangladesh, China, Thailand, Vietnam, and Ecuador, witnessed a dramatic loss of 51.9% of their combined mangrove area. A significant portion, 28% of the total mangrove lost, resulted from conversion to aquaculture, primarily for shrimp and fish farming.¹⁰ Fortunately, a recent positive shift towards reducing mangrove loss has occurred. This has largely been attributed to shrimp farmers realising the unsuitability of mangrove habitats for shrimp farms due to acidic soils, challenges in pond construction, and maintenance within the intertidal zone. As a result, new shrimp farms for semi-intensive and intensive culture have predominantly been constructed outside the intertidal zone.¹¹ New shrimp farm construction in mangrove areas has been mostly done by smallholder farmers hoping to increase their income with extensive shrimp farming, which has been encouraged by governments, NGOs and international organisations as a means to improve coastal livelihoods.¹¹

Mangroves have been removed and replaced by shrimp and fish ponds in Sangatta, East Kalimantan, Indonesia, only to be later abandoned as at this operation due to the unsuitability of the habitat for shrimp farming. Credit: Sukarman Karman, Getty.

The enforcement and success of legislation to protect mangroves and restore lost habitat has increased over the years, but it varies significantly between countries, regions, and provinces.¹¹ Preventing further mangrove deforestation for shrimp aquaculture while supporting impoverished coastal communities is an ongoing challenge that needs to balance environmental conservation with economic development and social well-being.¹²

Pollution

Shrimp ponds often discharge effluents containing excess nutrients, chemicals, and organic matter into surrounding water bodies and soil. This can lead to water pollution, causing oxygen depletion, algal blooms, and harm to aquatic ecosystems.¹³

Efforts to address water and soil pollution from shrimp farms include the voluntary implementation of Best Management Practices, standardised shrimp farming management practices created by different experts and organisations.¹⁴ They focus on optimising pond management, minimising the use of chemicals, and promoting sustainable farming methods, by providing guidelines for how to deal with issues like monitoring water quality, shrimp feeding regimes, managing waste water, and disease outbreaks.¹⁵ Additionally, the development and adoption of recirculating aquaculture systems (RAS) aim to reduce water exchange, limiting the release of pollutants into surrounding water bodies. However, if not managed properly, RAS can lead to the accumulation of nutrients and organic waste, creating conditions conducive to disease outbreaks and impacting water quality.¹⁶

While implementation and technological progress in creating healthier and environmentally sustainable shrimp farms has been made, challenges persist, and the effectiveness of these measures varies globally.

Caption: Shrimp farms from above in Sam Roi Yot National Park, Thailand. Credit: Kampee Patisena, Getty

Health

Poor water quality, feeding shrimp artificial or alternative live feeds, stress, shrimp exposure to new pathogens, and high animal density, often lead to disease outbreaks in shrimp farms. The situation is worsened by the lack of modern infrastructure, resources and enforcement of regulations in some of the largest producing countries.⁷ To prevent and combat outbreaks, farmers often use chemicals and antibiotics both reactively after outbreaks occur and also prophylactically to get ahead of disease. Not only do these also contribute to water pollution, potentially negatively affecting non-target species in neighbouring ecosystems, but they can also cause the emergence of antibiotic-resistant bacteria and the presence of antimicrobial residues in animal tissues, which pose health risks to both the individuals who handle, and consume the shrimp.⁷

Despite increased toxicological testing of imported shrimp by many importing regions, like the USA and the EU, budget constraints limit the testing to only a small percentage of the shrimp, leading to some shrimp sold in supermarkets and grocery stores having been found containing drug residues.¹⁷

Slavery and human rights abuses

Regrettably, the impact of shrimp production transcends environmental and health repercussions. Both wild-caught and farmed shrimp industries have been implicated in the use of slave labour and human rights abuses. To sustain high shrimp export rates at low prices, the industry has reportedly exploited vulnerable migrants seeking better lives, often tricked by traffickers offering seemingly legitimate work. Reports highlight instances of enslaved people facing violence and threats, with children often working alongside them.¹⁸

Learn more about the social cost of cheap seafood

Seafood supply chains are long and complex. From the moment the food is harvested or farmed until it lies on the consumer’s plate it will have likely passed through several players across different countries. This makes it challenging to trace despite numerous reports and legislations put in place.

In 2010, the European Union implemented a "carding system" to combat illegal fishing. Exporting countries are categorised with green, yellow, or red cards based on their policies regarding illegal fishing. A red card results in a ban on fisheries products from that country in the EU market. This system has been considered internationally successful as it encourages countries to regulate and monitor their fishing activities, tackling illegal fishing practices, and it can be seen as an example of how legislation can influence some of the industry’s issues.¹⁹ However, it falls short of addressing the humanitarian crisis of slave labour within the seafood industry. In 2022, the European Commission proposed a Forced Labor Regulation, which, as of November 2023, is still under development. Hopefully, it will be as successful at tackling humanitarian issues as the “carding systems” have been at tackling illegal fishing.²⁰

Which shrimp can I eat?

Whether it will even be possible to sustain an increasing cheap shrimp demand without it being socially or environmentally damaging, while unlikely, is still up for discussion. As it currently stands, however, a portion of the shrimp we eat in developed regions comes at the expense of slave labour and environmentally damaging practices. So what can we do?

Ceasing or reducing shrimp consumption and opting for sustainably and ethically produced shrimp are tangible actions we can take. The Marine Stewardship Council (MSC) label is given to seafood from fisheries and aquaculture that have been certified to meet certain standards pertaining to human rights and sustainability.²¹ But some have argued that the standards to acquire the label are too low and often poorly assessed.²² While it is still probably better to buy MSC-certified shrimp than non-certified shrimp, it’s important to keep in mind that these certifications are not without flaws.²³

Supporting local fishermen and community-supported fisheries can even be better alternatives, as smaller fisheries are more likely to employ lower-impact catch methods. Platforms like localcatch.org in the USA can help you find community-supported fisheries near you.

Fisherman holding a catch of freshly caught shrimp. Credit: Ali Barut, Getty

There are also a range of useful resources like the Monterey Bay Aquarium Seafood Watch website and the Good Fish Guide to help us make more informed decisions. These platforms offer science-based seafood recommendations, providing insights into the origin country of the food, the presence of chemicals and antibiotics and the fishing or farming techniques employed.

In conclusion, the shrimp industry's expansive growth has brought challenges that require a global commitment to sustainable and ethical practices. Navigating these complexities demands conscious decisions, advocacy for robust standards, and collaborative efforts across industries, governments, and communities, balancing the demand for shrimp with social and environmental responsibility.